On an operation of a construction machine, there has been typically known a technology of notifying an operator whether or not an energy-saving operation is in progress and requesting the operator to conduct an energy-saving operation.
For instance, Patent Literature 1 discloses a technology of turning a lamp on or off based on whether or not an open degree of an accelerator and an actual engine speed satisfy energy-saving operation conditions and of requesting the operator to conduct an energy-saving operation.
On the other hand, in vehicles (e.g. construction machines) including a diesel engine as a drive source, there has been known a construction machine provided with an exhaust gas purifying device for an internal combustion engine including a Diesel Particulate Filter (DPF) for removing particulate matters (PM) contained in the exhaust gas of the diesel engine.
In such a construction machine provided with the exhaust gas purifying device for an internal combustion engine, a regeneration treatment to burn the PM deposited in the DPF is widely performed. Specifically, there has been known a construction machine in which a guidance for requesting the regeneration treatment is displayed on a monitor device when the PM deposited in the DPF reaches a predetermined amount (see, for instance, Patent Literature 2).
Then, when the guidance for requesting the regeneration treatment is displayed on the monitor device and the operator conducts the regeneration treatment to the DPF of the exhaust gas purifying device in accordance with the guidance, the operator stops operations of working equipment and the like and holds the construction machine in an idling state.